Couple of build problems/questions

[asw20rr]

My airframe is together and I'm starting in on the electronics. I've run in to a couple things so far that I would welcome an opinion (or more) on:

I can't figure out what was intended with the design of the head block. It has a jesus bolt and two additional bolts which clamp it on the shaft. However if I tighten up the two clamping bolts it squeezed the phasing pins and the washout base will not slide up and down without great effort. Have others run into this and what did you do?

Is there any way to adjust the gear mesh (other than the little bit of slop between the round frame holes and bolts)?

Is there supposed to be something that will keep the boom from rotating in the frame other than the clamping force?

Thanks for the input,

Doug

[James Kovach]

Originally Posted by asw20rr

My airframe is together and I'm starting in on the electronics. I've run in to a couple things so far that I would welcome an opinion (or more) on:

I can't figure out what was intended with the design of the head block. It has a jesus bolt and two additional bolts which clamp it on the shaft. However if I tighten up the two clamping bolts it squeezed the phasing pins and the washout base will not slide up and down without great effort. Have others run into this and what did you do?

You do not need to crank those down so tight. Just crank them down far enough that your phasing pins will slide up and down freely. A little grease here is not a bad idea either. Just a light coating is more then enough. Just make sure you lock-tite those clamping bolts.

They use this design to keep the Head block from wearing and "wobbling" about the jesus bolt. It clamps the head to the main shaft for a much better attachment.

Is there any way to adjust the gear mesh (other than the little bit of slop between the round frame holes and bolts)?

No there is not. That is not really there to adjust gear mess. It is there to allow you to make sure everything in the clutch/drive stack is lined up properly. In other words, it allows you to get the clutch bell sitting on the clutch shoe squarely.

Is there supposed to be something that will keep the boom from rotating in the frame other than the clamping force?

No there is nothing there to do that. There really is no need if you tighten it down. I have 70+ flights on mine and not once has that boom rotated on me. Even when I have touched the tail during an Auto. If you are worried about it, you could always put a bolt thru the boom block and boom, but I really do not see a reason to do that.

IMHO, those "nubs and knotches" are more of a "location aid" than they are for keeping the boom from rotating.

[asw20rr]

Thanks James,

This build is scary quick and I think a lot of it is because of the lack of adjustability. Given the price (dare I say disposable) of the airframe and how well everything seemed to fit I'm happy so far.

I think my only gripe will be the head block. I like having the two clamping bolts plus the jesus bolt, but think it could have been worked out so that the phasing pin channels were not pinched by the clamping action.

Electronics will go in tonight. I am taking my wife out of town for her birthday this weekend, so don't know if this bird will make it in the air this week

[James Kovach]

Originally Posted by asw20rr

Thanks James,

This build is scary quick and I think a lot of it is because of the lack of adjustability. Given the price (dare I say disposable) of the airframe and how well everything seemed to fit I'm happy so far.

I think my only gripe will be the head block. I like having the two clamping bolts plus the jesus bolt, but think it could have been worked out so that the phasing pin channels were not pinched by the clamping action.

Electronics will go in tonight. I am taking my wife out of town for her birthday this weekend, so don't know if this bird will make it in the air this week

I wouldn't worry about it. You are putting too much thought into it. Just put it together and fly it. If I had any concerns with the airframe, believe me I would have said so in my review. I am totally happy with the Frenzy and it is getting more air time then any other heli I have because of how much I like it.

[mlucia]

Originally Posted by asw20rr

Thanks James,

This build is scary quick and I think a lot of it is because of the lack of adjustability. Given the price (dare I say disposable) of the airframe and how well everything seemed to fit I'm happy so far.

I think my only gripe will be the head block. I like having the two clamping bolts plus the jesus bolt, but think it could have been worked out so that the phasing pin channels were not pinched by the clamping action.

Electronics will go in tonight. I am taking my wife out of town for her birthday this weekend, so don't know if this bird will make it in the air this week

As with any pre-built heli make SURE you check all the bolts for locktite. Most all of them had little or no locktite on them.

While it is enticing that it is mostly built don't skip out on it!

There, that will add some time to your project

[asw20rr]

No delay on the locktite. I had already gone thru all the fasteners. About 1/3 needed locktite. I ended up doing 2/3 due to things I wanted to take apart, etc.

I got the build all done and test idled my (cheap off ebay, hope it is OK) used OS-50. Starts good and idles well. Hopefully I can sneak out to the club field tomorrow for a test hover

I'm looking forward to flying this heli! Stock Frenzy, OS50 Hyper, Century pipe, Hyperion DS20-FMD cyclics, 401 and DS20-GMD, cosmetic flaw Radix mains, stock tail blades, 2s lipo with CC bec, AR-7000. With a used engine and pipe, and a gyro off my bench, and some discount code shopping I'm into this build only about $650. Looks like a pretty good machine for the money

I'm not much for tuning nitro engines. What range of head/backplate temperatures should I be shooting for with and OS50?

Doug

[mlucia]

50 hyper? Main needle around 1 1/4 should be a good starting spot assuming it is already broken in. All mine are usually around 1 turn and a couple clicks and temps around 180-200ish on the head.

[asw20rr]

Thanks Mark,

I'm at 5300 feet so leaning out by turns of the needle (1 1/4) doesn't work very well for me. I do have a cheap infrared temp gauge and don't mind some trial and error.

[asw20rr]

A couple hover tests and two flights with the Frenzy on Sunday!

Things I need to work out:

1. I think the belt may be slipping. I did notice on a hard pitch pump that the tail seemed to stutter back and forth about 10 degrees. On lighter pitch pumps I had no such glitch. Has anyone had problems with belt slip and how tight are you running the belt. I've never had a belt this big before....
2. The tail performance is pretty lax. Stops are really mushy. I'm running a 401 and hyperion DS20-GMD. Headspeed might be a bit low, and I can adjust the travel a hair higher. Also, I need to work on the mechanical setup because I noticed it is off a fair amount in rate mode. Beyond that I'm not sure what to play with.
3. I have a rpm sensor coming for my eagletree. At this point I have no idea what headspeed I'm running. I started with it feeling too low and dialed it up till it seemed reasonable. Running a OS 50 Hyper, my throttle curve is pretty low. What is a good headspeed for a stock setup for sport flying moving towards light 3D?
4. I'm tail heavy. All the gear is pretty far forward. I'm only using a 2S 2100 lipo, so the battery is light and I'm using a Century pipe which is big and long. Any easy/cheap suggestions without adding weight???

Not too bad a list for my first nitro build from scratch. I think this heli will be just what I need. I flew my Vigor a couple flights to warm up and then surprised myself by being a lot more aggressive with the Frenzy than I planned. Even though I didn't have confidence in the tail it flew nice enough to push it a bit from the get-go!

Thanks for any and all help.

- Doug

[grnmac1]

give "Greggor" a call at amainhobbies (hes a sponsored pilot for amain) he is real knowledegeable on the frenzy. He is in tech support dept. (good guy!) he likes to talk

[James Kovach]

Tail issues you have stated above are probably most likely headspeed and gyro gain related. If you Headspeed is below 1800 RPM, you are not going to have a real SOLID tail. Hard pitch changes will cause a tail kick. You really have to crank the gain up to compensate for that with lower head speeds. Same with solid stops. The tail is not spinnning fast enough to give you the response.

Not sure how the Eagle Tree RPM sensor will work for you unless it works off a set of magnets or is optical. But I am sure you have that figured out

How did you check your COG? Empty tank? Full Tank? You should check it with a half full tank. As the tank empties, your COG is going to change. I personally never really get that crazy with the COG on a nitro for that reason. But to help, remove the Horizontal Fin. It is a "show piece" anyway.

[heartnspirit]

Hi Doug,

Glad to hear you're feeling comfortable with the heli! I think Sparx- is right on with his answer. You'll need to have 1900 rpm or more on your headspeed to get a solid tail. The tail has a 4.56:1 ratio over the main blades, so for every 100 rpm change of the main blades the tail speed changes 456 rpm. In other words with a headspeed of 1500 the tail is turning 6840 rpm but with a headspeed of 2000 your tail rotors are turning 9120 rpm and are MUCH more effective.
Leave the belt loose. I haven't heard of anyone slipping a belt yet. The A Main Hobbies sponsored pilot, Ben Storick flies with his very loose with no problems.
If you need to add weight a larger battery is a good way to go. You'll not only be able to get more flights in before recharging but with a higher capacity batttery you'll generally mantain higher voltages throughout all of your flights. Because you won't be discharging it so deeply it'll also be less demanding on your battery and it should last more cycles. Have fun!

[asw20rr]

Thanks guys,

Good to hear that belt slip is not an issue. I am using an eagletree optical rpm sensor on my JR vigor and it works out pretty well. I just used a permanent marker to mark sectors on the main gear. On the Frenzy I may need to use some white paint, but it should work out OK. I probably do have too low a headspeed, but having no idea what different headspeeds sound like on a 50 I need some instrumentation to check it out as I don't like to just dial things up without knowing. I know my gyro gain is up at like 92 with just a faint hint of wag, so yeah, probably low headspeed. I'm headed to a funfly Saturday so maybe will run into someone with an optical tach.

I checked the COG with an empty tank and it is tail heavy, so it will be even worse with fuel. The horizontal fin will go.... I'll also look for a beefier battery next time I have an order in to hobbycity or somewhere.

And I'll need to buy some more fuel!

BTW - James - I have not really quantified it yet, but my Vigor running an OS 61 appears to have pretty decent economy compared to the Frenzy, especially considering the HUGE weight difference. I'm going to stick with the Vigor for a while versus jumping ship to a Knight.

- Doug